BCS have a word for mermaid/siren though (sirena) so it's Mala Sirena. Which makes sense with the sea right there and proximity to Greece so Homeric legends about sirens will presumably be in the culture.

There's a nice song by Daleka Obala - Morska Vila. That's a first ring.

Makes sense. Maybe it's a bit like how informal English tends to use Germanic rather than Latin derivations?